A novel aadA aminoglycoside resistance gene in bovine and porcine pathogens
Cameron, A., Klima, C.L., Ha, R., Gruninger, R.J., Zaheer, R., McAllister, T.A. (2018). A novel aadA aminoglycoside resistance gene in bovine and porcine pathogens. mSphere, [online] 3(1), http://dx.doi.org/10.1128/MSPHERE.00568-17
Plain language summary
Aminoglycosides are important antimicrobials used worldwide for prevention and treatment of disease in a range of livestock animal species. The emergence of new resistance genes jeopardizes current pathogen detection and treatment methods. The risk of resistance gene transfer from animal and human pathogens is high when these resistance genes are carried on segments of DNA that can be easily shared between microbes. These mobile DNA segments are referred to as mobile genetic elements. In this study a new variant of a spectinomycin/streptomycin resistance gene that is found within a transmissible mobile element is identified and biologically characterized. The novel variant of the gene AAD(3″) encodes for a class of aminoglycoside-modifying enzymes and was discovered in pathogens isolated from samples taken from animals that suffered fatal complications with bovine respiratory disease. An examination of known bacterial pathogens of cattle identifies this gene in four different pathogen species.
A novel variant of the AAD(3") class of aminoglycoside-modifying enzymes was discovered in fatal bovine respiratory disease-associated pathogens Pasteurella multocida and Histophilus somni. The aadA31 gene encodes a spectinomycin/ streptomycin adenylyltransferase and was located in a variant of the integrative and conjugative element ICEMh1, a mobile genetic element transmissible among members of the family Pasteurellaceae. The gene was also detected in Mannheimia haemolytica from a case of porcine pneumonia and in Moraxella bovoculi from a case of keratoconjunctivitis. IMPORTANCE Aminoglycosides are important antimicrobials used worldwide for prophylaxis and/or therapy in multiple production animal species. The emergence of new resistance genes jeopardizes current pathogen detection and treatment methods. The risk of resistance gene transfer to other animal and human pathogens is elevated when resistance genes are carried by mobile genetic elements. This study identified a new variant of a spectinomycin/streptomycin resistance gene harbored in a self-transmissible mobile element. The gene was also present in four different bovine pathogen species.